fix some warnings

...sapo_fabric/server/task/fabric_handshake_accepting_task.h

common/cpp/src/system_io/system_io.cpp

...ples/producer/dummy-data-producer/dummy_data_producer.cpp

producer/event_monitor_producer/src/inotify_event.cpp

.../event_monitor_producer/src/system_folder_watch_linux.cpp

...tor_producer/unittests/test_system_folder_watch_linux.cpp

receiver/src/data_cache.cpp

receiver/unittests/test_datacache.cpp

tests/automatic/consumer/consumer_api/consumer_api.c

...sumer/next_multithread_broker/next_multithread_broker.cpp

tests/manual/performance_broker_receiver/getlast_broker.cpp